Yu.A. Zvezdina, A.N. Novikov, I.G. Tsyporina, A.I. Sherstobitov

One of the main trends in radar system development is the broadband system usage in radar, navigation and radio communication. Out of the wide range of problems connected to the broadband signal usage the problems of their spatial processing can be selected. The problems of finding the frequency dependence for the weight coefficients providing optimal spatial processing of the broadband signals according to signal/noise criterion can be considered as solved ones. The solution obtained would be optimal according to a range of other criteria. The obtained frequency dependencies have rather complicated form and due to that fact they can only be used in digital beamforming antennae. However, the optimal frequency dependencies can not be used there for the usage is connected to the defining and forming the weight coefficients in a continuous band. In the paper the quasioptimal frequency dependencies for broadband signal processing are investigated. The basic idea is to divide the frequency band of the signal processing into K subintervals, where the optimal dependency is approximated by rather simple functions. The paper aim is to investigate the influence of the quasioptimal spatial processing (subintervals quantity, K) on the broadband spectrum reconstruction accuracy in the cluttered environment for digital beamforming antenna. The investigations are carried out using the piecewise constant and piecewise linear kinds of approximation. The numerical simulation results for spatial processing of a broadband signal and broadband clutter signal in antenna array consisting of 100 elements at various values of processing parameters, K, are given and fully analyzed.